Analysis of climate variability in Rwanda as Indicated by temperature records since 1930s

Abstract

Near surface air temperature is one of the most important elements in weather and climate forecasting, so examination of its behavior is important for the understanding of climate variability which can vary spatially and temporally at local, regional and global scales. Various studies on air temperature recently indicated that the Earth’s near surface air temperature increased by 0.6°C – 0.8°C throughout the 20th century. This study analyzed climate variability in Rwanda since the 1930s until 2014 using the temperature records from 10 meteorological stations. The air temperature data were provided by Rwanda Meteorological Agency and quality control was performed on raw data before analysis using Excel 2007 and INSTAT Software. The analysis of maxima and minima indicated that trends of maximum of maximum air temperature were positive and significant at 8 meteorological stations whereas the trends for minimum of minimum air temperature at 10 meteorological stations were all positive and significant. For all parameters analyzed, Kigali Airport meteorological station indicated higher significance of the trends. The majority of meteorological stations presented an increase in both hot days and nights which confirm a warming in Rwanda over time. The analysis of average seasonal air temperature showed almost similar trends even though not all significant. This similarity in trends may be due to the fact that the short and long dry seasons intercept with rain periods in Rwanda.